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ArcticMyst Security by Avery

best wavelenght to ionize air

BowtieGuy

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Your 1st post, and you're trying to circumvent the BST rules, good start!

Reported!
 





diachi

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I got some magnets for sale.. Im strapped for cash.. it wont let me post in the wts thread.. help me out

hers my link

hamulicz23 | eBay


So ... circumventing B/S/T rules, by posting a sale in a thread that's completely unrelated to your sale. Not even an introduction?

Doesn't give me much confidence as a potential buyer...

Also reported.
 

CurtisOliver

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Wow, did any of you actually check out what he was selling?
If you did, then I wouldn't trust him as a seller at all. :p

Large Neodymium magnets N48 3 inchx1.5 inch very Strong 630 Lbs force Free shipp

He has accidentally stuck two 285kg magnets together. He has clearly tried and struggled to separate them, damaging the magnets in the process. And now he is expecting people to buy them and separate them themselves with a wooden contraption.

Things like this just make me want to laugh! :crackup:

17abd03d320eba95f0f3446bda5c3f31_what-meme-13-cranky-coder-what-meme_480-360.jpeg


2x 285kg pull magnets with a total combined attraction of 570kg would have a slide resistance of at least 114kg. There is no way you are separating them without damaging the magnets further.

Oh, and how do you think he is going to ship these magnets? :whistle:

How he didn't hurt himself in the process I don't know. You can see that he tried adding a wooden spacer and the magnets have crushed it unsurprisingly.
 
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diachi

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I noticed that too Curtis, although I had a hard time telling if those were in fact chips on the magnets or something sandwiched between them, some sort of plastic perhaps. "Like new" didn't seem accurate!

Never even considered how you'd ship these... In the middle of a big box? :D
 

CurtisOliver

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It looks to me to be damage to the protective plating on the magnets. Shifting over 100kg would be a challenge with basic tools. :D
Ha, like new. :crackup: I laughed at that. Yes they came stuck together with wood sandwiched in between them and damage to the sides. :thinking:
Probably would have to shipped in a big box. I think they have to have special handling requirements as well.
 
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Go back and look at the thread content. Read the responses.
Necroposting is STRONGLY discouraged on the form.
 

WizardG

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There is a way to separate them. Discharge them. Then recharge them.

Considering how low the curie temperature is for NIB magnets that's probably the best solution. Put 'em in an oven set for 250 or 300 for an hour or so and they should fall apart.
 

tedcs

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1064nm is one of worst possible choices for ionizing air becose the absorption is very poor at this wavelenght,no wonder you need 1000s of watts.And thats exactly why I want to use wavelenght that is much more efficient so I dont need such powerfull laser
I'll throw in my two cents, which is all that all I have.
Get some 150 pound capacitors.
Determine the dimensions and mass of the piece of air you wish to make incandescent.
It takes one nanosecond to produce a piece of light one foot long.
Find, at any wavelength under consideration, the air's specific absorption and specific heat.
Determine the joules / second required to absorb sufficient energy to cause incandescence.
Multiply those answers together and divide by the cost to yield figure of merit.
Wild guess: oxygen absorption
Exotic colors/frequencies probably not worth considering
Can you locate a phased plasma rifle in the 40 watt range?
Light Sabers are not available, yet.
 

OzMaverick

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NdYAG at 1064 nm and 100 ns pulse length with 2 J of energy works. So does 532 nm 100 ns and 1 J. I get air breakdown routinely by focusing the beam.
 
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I have some experience with this topic.

The idea was not to fully ionize air with a laser, but to rather promote dielectric breakdown of air using light. So, create a large difference in charge between two objects, just below the point where the air in the gap between them would breakdown, and then flash some light into the gap and lower the dielectric breakdown strength of the air just enough to trigger a flashover. To be honest, I didn't expect it to work at all, but we did show that it was possible, although the results were so inconsistent that I'm not sure what was going on.
 




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